EN - 46
Failure Diagnosis
Failure Diagnosis of Gas Cooler Fan
(1) When the ground fault protector shuts OFF.
1. Check the insulation resistance between each terminal of the power supply unit, fan motor inverter-PCB
(hereafter, inverter-PCB) and the ground (G terminal).
..... When the insulation resistance is 1 M
Ω
or below, insulation failure exists in the inverter-PCB or fan motor.
2. Disconnect the fan motor lead wire from the inverter-PCB and check the insulation resistance between the
ground.
..... When the insulation resistance is 1 M
Ω
or below, insulation failure exists in the fan motor.
(2) When the fan motor does not rotate normally.
1. While the fan motor is powered, it does not rotate smoothly (stopping or uneven rotation) or generates roaring
noise.
..... Fan motor bearing failure is the cause.
Electronic expansion valve (MOV3) Operation Check
(1) Align the rotary switch (knob) with [DIS] and check the discharge gas
temperature of the compressor.
(2) Set the DIP switch SW13-5 to [ON], and rotary switch (knob) to [ON]
(valve opening
fi
xed mode) and set the electronic expansion valve opening
to 450 steps.
At this time, check that discharge gas temperature slowly goes down.
Before checking the electronic expansion valve operation, if the valve has been
operating with a full opening (480 steps), discharge gas temperature does not
change. Wait for some time and then check.
If the electronic expansion valve is fully open, then refrigerant pipe clogging is
the possible cause.
Caution
All normal
DIP switch SW13
ON
OFF
High pressure/low pressure
service valves
Split cycle electronic
expansion valve (MOV3)
Compressor
01̲OCU-CR200VF5.indd 46
01̲OCU-CR200VF5.indd 46
2018/12/28 15:17:15
2018/12/28 15:17:15
